Color filters, especially those for solid image forming devices such as charge-coupled devices (CCD) and liquid crystal display devices (LCD) are used for forming a pattern of three primary colors (red, green and blue) or three complementary colors (yellow, magenta and cyan) on a transparent or opaque substrate. Regarding the photosensitive resin compositions for such color filters, JP-A-4-175753 and JP-A-4-175754 disclose respectively a photosensitive resin composition for color filter comprising (A) a novolak resin obtained by polycondensing a phenolic material containing 50 mol % or more of bisphenol A and an aldehyde, as an alkali-soluble resin, (B) a light-modifiable dissolution inhibitor, (C) a dye soluble in the solvent (D) and compatible with the resin (A), and (D) a solvent, and a composition comprising (A), (B), (D) and (C') a particulate pigment.
However, use of such positive photosensitive resin compositions for color filter involves the problems of change of pattern shape and discoloration of color filter because of high-temperature and long-time heating that is required after pattern formation.